So it turns out my 2 day old 2013 Chevy Malibu is one of the dreaded ones made under the forged piston casting issue. a bulliten found about 5 pages back on this forum. A check at the dealer yesterday found no issues but for some reason feel weird about it. That said the car runs well and is smooth and quiet. After driving my wife's new Chevy Cruze a few times my old 99 suburban just wasn't cutting it anymore. possible engine issue aside, It is a nice ride and if your looking for a mid size car its worth checking out the new Malibu . The nly shortcoming to me is well the engine... As a previous owner of a 2006 Malibu the 3.5 V6 was a nice powerplant with some punch. The 2.5 4 while smooth has not much "punch" Maybe some Premium fuel and a K&N filter might improve response. at 640 miles on the clock the mileage is 26MPG.